Low Energy Gasifier-Liquefier

ABSTRACT

Disclosed are two related devices which can convert gas to and from liquid, or liquid to and from gas, with no expenditure of energy for heat of vaporization or for condensation. One device is designed for discrete units of fluid, the other for continuous flow. Both devices can be made fully enclosable. Both devices can compress an uncompressed vapor an arbitrary amount without additional energy. Applications include chemical separation, vapor compression, water purification, heat engines and power generation.

CROSS -REFERENCE TO RELATED APPLICATIONS

Related Patents have attorney docket numbers wakelley01, wakelley02, and wakelley03, wakelley04 and are listed below as Patent A, Patent B, Patent C and Patent D, respectively.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

This patent is not federally sponsored.

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

Many processes require a fluid make a transition from gaseous state to liquid and back, or from liquid to gaseous state and back. These include chemical separation, compression, water purification, and power generation. This is an energy intensive process, as simple methods for boiling and condensing both take large amounts of energy. However, the initial state (temperature) and final state of the fluid's are generally the same, or can be. A mechanism capable of boiling a fluid, then saving the energy by boiling a second fluid while liquefying the first allows the same energy to be used to gasify, liquefy, then gasify, or liquefy, gasify, and liquefy, is theoretically possible, as long as the energy quantities are matched.

Related Patents have attorney docket numbers wakelley01, wakelley02, and wakelley03, wakelley04 and are listed below as Patent A, Patent B, Patent C and Patent D, respectively.

BRIEF SUMMARY OF THE INVENTION

Two devices are disclosed with similar purpose. One handles discrete quantities of fluid, the other handles continuous flow. Patent A, Patent B, Patent C, and Patent D in combination, can liquefy then gasify the outflow of a steam generator. The systems as is will recycle most of the water and heat. The devices described here use the same principles, but are specifically designed to be able to run as a closed system. This would meet a zero emission requirement. It would also allow steam generation plant to be operated economically in regions where water is scarce. A second class of devices is introduced, with the ability to cycle discrete quantities, and also can run as a fully enclosable system. An example application would be power generation from heated oil or liquid salts from a solar collection plant located in a desert. It could eliminate the need to pipe the heated fluid, as well as reduce the danger exposed when piping extremely hot materials.

Both devices are capable of cycling a fluid to and from gas state with a hot reservoir, or to and from liquid state with a cold reservoir. In addition, a small heat pump is included which can restore precise beginning conditions of the cold or hot reservoir.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 shows a diagram of a discrete liquefier and gasifier. This device uses 2 paired liquid and vapor chambers, each with opposing pistons, and a 5th expanded vapor chamber.

-   #1 Coupling rod for opposing pistons. -   #2 d Reservoir Liquid piston, down position. (Full liquid reservoir) -   #2 u Reservoir Liquid piston, up position (Empty liquid reservoir). -   #3 d Target liquid storage, down position (full). -   #3 u Target liquid storage, up position (empty). -   #4 d Reservoir Vapor storage, down, emptiest position. Vapor     chambers must be larger than liquid chambers. Forces still balance     due to identical piston area for vapor and liquid. -   #4 u Reservoir Vapor storage, up position, reservoir fully converted     to vapor. -   #5 d Target Vapor compressed storage, down position, target fluid     being liquefied or fully liquefied. -   #5 u Target Vapor compressed storage, up position, Target fluid     fully vaporized and compressed. -   #6 d Simple valve to select between uncompressed vapor storage and     compressed vapor storage. -   #6 u Simple valve, opposite position. -   #7 Heat exchanger insulated container. -   #8 Heat exchanger, counter flow heat exchanger, such as low cost     counter flow heat exchanger from Patent A. Sized for material,     temperature range and flow rate ideally 90+% transference -   #9 Target Fluid compressed vapor storage, a cylinder sealed by a     piston. -   #10 Reservoir Vapor storage, a cylinder sealed by a piston. -   #11 Target Liquid Storage, a cylinder sealed by a piston. -   #12 Reservoir Liquid Storage, a cylinder sealed by a piston. -   #13 All connecting tubing—insulated, temperature and pressure rated     for materials in use. -   #14 Uncompressed Target Vapor Storage, a large cylinder sealed by a     piston. -   #15 Uncompressed Target Vapor piston.

FIG. 2 shows same view as FIG. 1, with movable components in opposite positions. Annotated parts are the moving parts. Redundant annotations omitted for clarity.

FIG. 3 and FIG. 4, Perspective views of same device.

FIG. 5 and FIG. 6, Perspective views of same device, movable parts in opposite positions.

FIG. 7 shows magnified view of heat exchanger managing the vapor to liquid transitions. By controlling the Fluid Levels, the direction of heat flow, which fluid is liquefied and which gasified are also controlled.

-   #1 Low Fluid Level for gas being liquefied. -   #2 High Fluid Level for liquid being gasified -   #3 Vapor (gas) counter flow heat exchange -   #4 Liquid counter flow heat exchange -   #5 Liquefaction/gasification counter flow region

FIG. 8 shows the basic block diagram of a continuous flow liquefy/gasify cycle. The diagram has Thermal Pressure Multiplier, Low Cost Counter Flow Heat Exchangers, and Fluid Pressure Ladder and Steam Generation cycle of Patents A, B, C, and D.

-   #1 Shows Low Cost Counter Flow Heat Exchanger, linked with -   #2 a 2 or more stage Fluid Pressure Ladder, to create a Thermal     Pressure Multiplier. -   #3 liquid Reservoir -   #4 Boiler or Heat addition -   #5 Turbine/generator -   #6 Path for heat pump to make enclosable -   #7 Path for excess heat if enclosability not required -   #8 Fluid paths coupling heat exchangers and pressure ladder

DETAILED DESCRIPTION OF THE INVENTION

Both devices are based on a combination of counter flow heat exchangers (Patent A) and reservoirs of heat or cold. (Technically a cold reservoir is more accurately described as having less heat).

The fluids should be matched in thermal capacity. With the same type of material in both chambers, this simply means an equal mass of fluid. It would simplify the system to have a reservoir that remains in liquid state, if a material is available that is liquid over the required temperature range.

If liquid is to be cycled to gas and back to liquid, a hot fluid reservoir is required.

If a gas (vapor) is to be cycled to liquid and back to gas, a cold fluid reservoir is required.

In either case, optimal efficiency will be when the reservoir temperatures are just above or just below the boiling point.

The reservoir temperature is independent of the temperature of the fluid to have phase changed. It simply must have enough heat or cold capacity to supply or exhaust the heat of the incoming fluid, and change of state.

Ideally the incoming liquid or vapor will also be near the boiling point.

Each reservoir has a piston to facilitate movement of the fluid. The piston is coupled to a second empty storage chamber, in a manner that pressure in each storage chambers are in balanced opposition.

A similar reverse arrangement is made on the incoming fluid side.

Typical fluids may be 100 to 1000 times denser than their vapor at STP. To avoid extreme pressures, the gas storage chamber must be larger than the liquid. For example, if the density multiple of a liquid to its vapor is about 600, a gas chamber three times the size of the liquid chamber would yield a density of 200× density at STP.

Opposing pistons make fluid movement force independent of pressure. The vapor reservoirs must be larger in volume than the liquid reservoirs, but the area of the pistons must be the same, to equalize force. The reaction is begun by filling one side of counter flow heat exchanger with liquid and the other with vapor. Piston positions determine flow and direction of state exchange. If compression is required, a 5th, larger chamber of vapor will hold initial uncompressed target vapor. A simple valve switches connection of the target side of counter floe heat exchanger between the large uncompressed chamber and the small compressed target chamber.

Pressure in the system depends on temperature for all gases (vapors). Consider an application which first drops vapor temperature to 90 degrees, with a boiling point of 75. The cold liquid reservoir must be 60 degrees or colder to insure complete phase change.

Phase change is achieved via controlled flow on each side through the heat exchanger in opposite directions. The heat exchanger should be oriented vertically, liquid phases at bottom.

It is sufficient to insure complete phase change if the fluid being liquefied is not allowed to rise into the heat exchanger, but moved at a speed to keep liquid phase level at the bottom end of the heat exchanger, and to insure the liquid level of the other fluid being gasified, is maintained near the top of the heat exchanger. This insures heat flow from gas phase to liquid phase throughout the heat exchanger.

Completion of the level monitoring phase is done when target fluid is completely phase changed.

At this point, the expected benefit has occurred or will occur on the opposite phase change. Reverse phase change can begin immediately.

Reverse phase change requires flow directions from storage chambers of each fluid is reversed. The level monitoring control is the same, but liquid levels are reversed between target and reservoir sides.

At this point the benefit has been realized.

Benefits might include a) drastic reduction of a gas's (vapor's) volume without doing work of compression, separation of a mixed vapor into its components by boiling point, removal of contaminants from a liquid (e.g. distilled water).

The last step is to restore initial reservoir temperature, which will have moved toward the boiling point. Counter flow heat exchangers can approach 100% but not achieve it. To the extent heat was incompletely switched between the fluids, the heat reservoir temperature needs to be adjusted.

The hot reservoir can be adjusted by pumping heat from the liquid outflow into the hot reservoir. This is a very small adjustment relative to the energy of vaporization or condensation. Ideal setup will have intake and outtake as near boiling point as possible.

Adjusting the cold reservoir uses the same strategy, but instead pumps from the cold liquid reservoir into the hot fluid vapor outflow. Again, temperature differences will be small, so heat pump has a small amount of energy to move, compared to heat of Vaporization.

After operation of the heat pump, vapor based or thermoelectric device, the system is restored to its initial state and ready for the cycle to repeat.

A continuous flow system requires two sets of discrete devices operated on opposite phases, or the components of Patent A, Patent B, Patent C and Patent D connected as a Counter Flow Heat Exchanger coupled to a Fluid Pressure Ladder to make a Thermal Pressure Multiplier (FIG. 8). Previous Patent disclosures did not describe creation of enclosable fluid envelope or fully enclosable, including heat flow.

To make a closed fluid system, fluid tight connection must be made between all components, such as Turbine and Heat Exchanger's intake, and Heat Exchanger's outtake and the reservoir, and the Reservoir must be enclosed as well. This is sufficient for enclosed fluid system, but also requires temperatures remain stable, within an operating range.

For a Vapor to Liquid to Vapor system, the necessary component to run fully encapsulated is to add a second Heat Pump connecting the reservoir to the pre-heated (by recycled heat) fluid. Since the middle of the temperature gap will include a phase change, this is actually a very small temperature rise. The Heat Pump does not need to be 100% efficient, as any added energy will end up in the pre-heated fluid, pre-heating it further.

For a Liquid to Vapor to Liquid system, the same can be done by pumping heat from a liquid outtake into a hot vapor reservoir. Again, heat pump inefficiency is also pumped to the hot Reservoirs, where the energy is desired. (So no energy is lost).

For a closed Vapor system, such as a steam generator, it may be more convenient to use ambient air to stabilize (cool) the reservoir temperature. This would reduce energy efficiency by the amount of heat lost, but would be a cheaper and much simpler system, requiring no heat pump.

Operation of continuous flow system requires only equal inflow and outflow, a rate allowing heat to be nearly completely transferred, and a series of heat exchangers sufficient to perform complete temperature exchange.

Operation of the discrete quantity device is by fluid level. The liquid fluid level is risen by lifting that dual piston until fluid is at the desired point in the vertically oriented counter flow heat exchanger. The fluid level on the gas side is similarly maintained at a physically lower point in the counter flower, by moving dual pistons down. In the case of liquefying a large volume, the pressure the gas is normally under keeps the counter flow heat exchanger filled with vapor exposed to temperatures which will cause condensation. It will take some time to condense enough fluid to reach the desired fluid level. As the vapor liquefies, the pressure drops to near zero, or volume drops to near zero under constant pressure.

Energy used by the system is 1) sufficient energy for movement of the mass of the fluids and friction and 2) sufficient to power a small heat pump to stabilize the Reservoir Temperature. Thermoelectric devices are ideal for the heat pump device. The much larger heat energy of vaporization (and energy given by condensation) are conserved and reused. 

1. This patent document discloses a pair of devices that can transform gas to liquid and back to gas phase, or liquid to gas and back to liquid phase.
 2. Devices cited in claim 1 devices use a small fraction of what otherwise would be the energy to condense via conventional heat pump, and heat of vaporization through heat pump or direct heat source.
 3. Device A cited in claim 1 can run in continuous flow.
 4. Device A cited in claim 3 can work with a single fluid, or two separate bodies of fluid.
 5. Device A cited in claim 4 can produce distilled water while generating power.
 6. Device B cited in claim 1 is optimized for converting a discrete quantity of fluid.
 7. Device B cited in claim 6 can compress vapors by a factor up to the ratio of the density of the liquid to the density of the uncompressed vapor. (For Nitrogen, by a factor of 600), with effectively no energy expended.)
 8. Both devices cited in claim 1 can completely return the internal device system to its original state.
 9. Both devices cited in claim 1 are enclosable and so do not depend on being in an atmosphere, or on external heat or cold sources.
 10. Both devices cited in claim 1 can be insulated to operate in an adverse temperature environment.
 11. Both devices cited in claim 1 can be operated in a vacuum, provided the fluids are not exposed to the vacuum.
 12. Neither device cited in claim 1 are affected by outside pressure nor temperature (unless deliberately exposed for desired effect).
 13. Device cited in claim 3 differs from prior Patents in that full target vapor enclosure is possible, and that a small heat pump is added to stabilize reservoir temperature.
 14. Both devices cited in claim 1 require only sufficient energy to move the mass of the fluid, overcome mechanical resistance internal to the device, and operate a heat pump to correct for counter-flow heat exchanger efficiency, to the extent it is less than 100%.
 15. Both devices cited in claim 1 can achieve compression of an arbitrary amount without additional energy for additional compression. 